<?
switch ($_GET[c1]) {
    case $_GET[c1] >= 2:
        $discount1=0.95;
		break;
    case $_GET[c1] >=5:
        $discount1=0.9;
		break;
    case $_GET[c1] >=10:
        $discount1=0.85;
		break;
    case $_GET[c1] >=50:
        $discount1=0.8;
		break;
	default:
		$discount1='1';
}
switch ($_GET[c2]) {
    case $_GET[c2] >= 2:
        $discount2=0.95;
		break;
    case $_GET[c2] >= 5:
        $discount2=0.9;
		break;
    case $_GET[c2] >= 10:
        $discount2=0.85;
		break;
    case $_GET[c2] >= 50:
        $discount2=0.8;
		break;
	default:
		$discount2='1';
}

if($_GET[c1]<>null){echo $c_a_1 = round(210*$_GET[c1]*$discount1);}
if($_GET[c2]<>null){echo $c_a_2 = round(399*$_GET[c2]*$discount2);}
if(isset($_GET[t1])){echo $_GET[t1]+$_GET[t2];}
?>